Stability-indicating HPLC Assay Method and Degradation Profile of Tamsulosin

A sensitive, stability-indicating liquid-chromatographic method for analysis of tamsulosin in the presence of its degradation products has been developed and validated. Efficient chromatographic separation was achieved on a C18 column with a simple isocratic mobile phase consisting methanol: 50 mM phosphate buffer (pH 7.8, ratio 80:20) at a flow rate of 1 ml/m. The linearity of the method was excellent over the range 5-250 μg/ml. The method was sensitive, with low limits of detection (10 ng/ml) and quantification (50 ng/ml). The recovery of the method was consistently good (99.5–101.9%) with low (<1%) intra-day and inter-day relative standard deviation. Robustness studies confirmed that peak area was unaffected by small changes in temperature and mobile phase composition. Forced degradation was performed in methanolic solution. In alkaline medium the drug was degraded rapidly as compared to acidic and oxidative condition. The validated, stability-indicating, method was used for analysis of tamsulosin in pharmaceutical dosage form and also to reveal the hydrolytic degradation profile of the tamsulosin.